The present invention relates generally to methods of forming structured sintered articles and particularly to methods of forming structured sintered articles comprising one or more of glass, ceramic, and glass-ceramic particles. The disclosed method has been particularly developed for and may be particularly useful in the manufacture of microfluidic devices and similar structures.
Associates of the present inventors have previously developed techniques for forming glass rib structures, as disclosed for example in U.S. Pat. No. 5,853,446, and related methods for producing microfluidic devices, as disclosed for example in U.S. Pat. No. 6,769,444, both of which are assigned to the Assignee of the present application. These previously developed methods include, among other steps: providing a mixture of a binder and sinterable particles, such as glass, glass-ceramic or ceramic particles or mixtures thereof; molding the mixture to form a desired structure; setting and demolding the structure; and debinding and sintering the structure. Setting is performed by heating the mixture for thermosetting binders, by cooling or allowing the mixture to cool for thermoplastic binders, or by irradiating the mixture for radiation-curable binders. In U.S. Pat. No. 5,853,446 is disclosed that radiation-curable binders may take the form of “hybrid” binders—mixtures of radiation-curable binder materials and thermoplastic binder materials—providing fast radiation-setting and at the same time achieving a more complete debinding or “burnout” of the binder similar to that of thermoplastic binders. In the purely UV or hybrid UV binder embodiments, fast-setting by irradiation is used while the mixture is in the disclosed roll mold and/or simultaneously with removal of the mixture from the roll mold, in order to set the structure and aid removal of the structure from the mold.